Prostate cancer (PCA) is the most frequent male cancer and a leading cause of cancer death in US. Most elderly men harbor prostatic neoplasia with the vast majority of cases remaining localized and indolent without need for therapeutic intervention.
Current methods of stratifying tumors to predict outcome are based on clinicopathological factors including Gleason grade, PSA, and tumor stage. Although these formulae are helpful, they do not fully predict outcome and importantly are not reliably linked to the most meaningful clinical endpoints of risk of metastatic disease and PCA-specific death. This unmet medical need has fueled efforts to define the genetic and biological bases of PCA progression with the goals of identifying biomarkers capable to assigning progression risk and providing opportunities for targeted interventional therapies. Genetic studies of human PCA has identified a number of signature events including PTEN tumor suppressor inactivation and ETS family translocation and dysregulation, as well as many other important genetic and/or epigenetic alterations including Nkx3.1, c-Myc and SPINK. Global molecular analyses have also identified an array of potential recurrence/metastasis biomarkers, such as ECAD, AIPC, Pim-1 Kinase, hepsin, AMACR, and EZH2. However, the intense heterogeneity of human PCA has limited the utility of single biomarkers in the clinical setting, thus prompting more comprehensive transcriptional profiling studies to define prognostic multi-gene biomarker panels or signatures. Furthermore, the clinical utility of these predictive signatures have remained uncertain due to the inherent noise and context-specific nature of transcriptional networks and the extreme instability of cancer genomes with myriad bystander genetic and epigenetic events producing significant disease heterogeneity. These factors have conspired to impede the identification of biomarkers capable of accurately assigning risk of disease progression. Accordingly, a need exists for more accurate models of human cancer that can be used together with complex human datasets to identify robust biomarkers that can be used to predict the occurrence and the behavior of cancer, particularly at an early stage.
In this invention, we have generated new engineered mouse models of prostate cancer and identified genes and pathways associated with prostate cancer progression. This model, coupled with comparison of human data and functional validation, has led to discovery of many new therapeutic targets as well as prognostic markers with strong clinical relevance in metastatic cancer.